Expansible earth anchor



Oct. 8, 1940.

c. E. HANDEL EXPANSIBLE EARTH ANCHOR Filed June 15, 1939 liven/for Patented Oct. 8, 1940 UNITED STATES PATENT OFFlCE Application June 15,

1 Claim.

My invention relates to' that class of earth anchors having a series of anchor blades pivoted at their lower ends to a base, and having means for forcing the blades outwardly and locking them in their expanded positions.

The object of my invention is to provide an earth anchor of this class, of simple, durable and inexpensive construction and including a brace plate for expanding the anchor blades, the blades being connected to the brace plate in such manner that in all positions of their pivotal movement relative to the base they are held against movement away from the brace plate and are slidingly connected thereto so that during the expanding movement of the blades they are all moved to the same extent and in any position of such movement they are held against further movement outwardly by the brace plate, and when the blades have been fully expanded they will be locked to the brace plate to thereby avoid the possibility of having one blade expanded to a greater extent than the others, so that when excessive strains are applied to the anchor rod these strains will be equally borne by the blades, thereby avoiding the possibility of applying a major portion of the strains upon one blade which has been expanded more than the others.

In the accompanying drawing Figure 1 shows a side elevation of my improved earth anchor in its collapsed position;

Figure 2 shows a plan view of the brace plate, a portion of one anchor blade being shown in section and slidingly held to the brace plate;

Figure 3 shows a side elevation of one of the anchor blades showing its upper inner surface;

Figure 4 shows a detail vertical sectional View of a portion of the base, one anchor blade pivoted thereto, a portion of the brace plate locked to the anchor blade, and the anchor rod;

Figure 5 shows a plan view of the base; and

Figure 6 shows a sectional view of the base on the line 6-6 of Figure 5 and showing an anchor blade pivoted thereto.

The base is indicated by the reference numeral [0 and has three pivot bars ll fixed thereto; a nut I2 is fixed to the under portion of the base.

The anchor rod 13 is extended through the base and nut and is threaded.

The brace plate comprises a tubular central member l4 slidingly mounted on the anchor rod, and a nut Ma is mounted on the anchor rod and engages the top of the member M.

The body 15 of the brace plate is extended outwardly from the member I4 and is formed with reinforcing braces l6. At three equally 1939, Serial No. 279,286

spaced apart sides of the brace plate are the guiding lugs ll, having their ends tapered away from the brace plate and outwardly. The inner surface of each lug is extended downwardly at 2| forming a locking lug.

5 The blades are indicated generally by the numeral I9 and are pivoted at their lower ends to the pivot bars I I. On the upper inner surface of each anchor blade is a dove-tailed groove 20 substantially conforming to the guide lugs ll. At the lower inner end of this groove is a locking shoulder Hi to co-act with the adjacent guiding lugs I1, and at the upper outer portion of the groove 20 is a laterallyenlarged portion of the groove through which the lugs ll may be inserted into the groove 20.

In practical operation, and assuming that the anchor is in the position shown in Figure 1, it is then inserted in a hole in the earth and then the anchor rod is rotated, thus moving the anchor rod downwardly through the nut 12. As this movement progresses all of the anchor blades are moved outwardly to a uniform extent, the dove-tailed groove and the tapered lugs prevent any independent movement of any of the anchor blades. When the anchor has been fully expanded, the co-acting locking lugs l8 and 2| cause the plate [5 to serve as a rigid brace for the blade, preventing further outward movement thereof. Heretofore it sometimes happened that one of the blades became expanded to a greater extent than the others and became fixed in that position, then when excessive strains were applied to the anchor rod, a major portion of such strain was applied to one blade only and the blade was broken. This cannot occur with my present anchor because all of the blades are uniformly expanded, and when in use strains upon the anchor rod are equally distributed upon the blades.

I claim as my invention:

An earth anchor, comprising a base, a series of blades pivotally connected to the base and extended upwardly and outwardly therefrom, each blade having on the upper inner surface a longitudinally arranged dove-tailed groove, an anchor rod connected to the base, a brace plate slidingly mounted on the anchor rod and having at its outer edge a bracing and guiding lug for each blade, said lug being extended into the dovetailed groove of the adjacent blade, whereby the blades rotate on their pivots and are held against either inwardly or outwardly independent movement.

CHARLES E. HANDEL. 

